Automatic land leveler



May 19, 1942- w. F. L ETHLEAN 2,283,744

AUTOMATIC LAND LEVELER Filed May 8, 1941 2 Sheets-Sheet l .N ENTOR a' yrwf@ WITNESS ATTORNEYS May 19, 1942.

W. F. LETHLEAN 'AUTOMATIC LAND LEVELER Filed May 8, 1941 2' Sheets-Sheet 2 ATTORNEYS Patented May 19, 1942 UNITED STATES PATENTOFFICE AUTOMATIC LAND LEVELER William F. Lethlean, Haines, Oreg., assigner of one-half to F. D. Baird, Baker, Oreg.

Application May 8, 1941, Serial No. 392,567

l sired, and may be of any length and spaced any 4 Claims.

This invention relates to an automatic land leveler and has for an object to provide apparatus of this character in which the lowering of the supporting wheels as they drop into a depression causes the scraper blade to be raised, and raising of the supporting wheels as they are elevated on a hump causes the scraper blade to be lowered.

A further object is to provide simplified means for effecting angular adjustment of the scraper blade.

A further object is to provide vertically adjustable head and tail boards forming gauges assembled with the runners, the tail board being adapted to rock up when encountering stones or other obstructions.

A further object is to provide spaced longitudinal runners which support the various parts, and which are reinforced against distortion by brace rods on either side of the center and by crossed rods adjacent either end.

A further object is to provide a device of this character which will be formed of a few strong, simple and durable parts, which will be inexpensive to manufacture, and which will not easily get out of order.

With the above and other objects in view, the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacricing any of the advantages of the invention.

In the accompanying drawings forming a part of this specification:

Figure 1 is a plan view of an automatic land leveler constructed in accordance with the invention.

Figure 2 is a longitudinal sectional view taken on the line 2-2 of Figure 1, showing the scraper blade lowered as the supporting wheels are raised.

Figure 3 is a view similar to Figure 2, but showing the scraper blade raised as the supporting wheels are lowered.

Figure 4 is a longitudinal sectional view of the device.

Figure 5 is a cross sectional view taken on the line 5-5 of Figure 1.

Figure 6 is a cross sectional view taken on the line 6-6 of Figure 1..

Referring now to the drawings in which like characters of reference designate similar parts in the various views, III designates a pair of rundesired distance apart. A pair of transverse braces II are connected to the runners near the center thereof and the runners are connected together on either side of the center by crossed brace rods I2 and I3. The brace rods hold the runners rigidly in spaced relation.

A pair of supporting wheels I4 are disposed outside of the runners and are mounted upon an axle I5. The axle is mounted in bearings I6 on the end s of beams I1, which extend forwardly toward the front end of the device, and at the front ends are pivotally mounted on the upper ends of bracket arms I8 through the medium of respective pivot pins I9. The bracket arms are secured in upright position on the runners by bolts 20. Thus, the supporting wheels may move upwardly and downwardly relatively to the runners as the machine is drawn forwardly by a tractor or other means.

A scraper blade 2| is mounted to extend transversely between the runners in rear of the supporting wheels, and the distance rearwardly of the supporting wheels is determined by the speed at which the device is to be driven, twenty inches being preferable for a predetermined three mile per hour speed. Superposed pairs of links 22 and 23 are pivotally connected at their forward ends to the rear face of the blade at the top and near the bottom thereof by pivot pins 24 and 25. The rear ends of the links are pivotally connected to respective upstanding levers 26 by pivot pins 27 and 28. The levers 26 are pivotally mounted on the runners through the medium of bracket arms 29 which are bolted to the runners, as shown at 30, and pivot pins 3| are engaged through the free ends of the bracket arms and through the levers 26 between the Superposed links 22 and 23. When the upstanding levers 26 are rocked, the angular inclination of the blade to the ground is varied. The means for rocking the levers 26 will be presently described.

For connecting the blade and the supporting wheels for simultaneous movement vertically in opposite directions, bell crank levers 3| are pivotally connected at their elbows 32 to upstanding bracket arms 33, which are secured to the runners by bolts 34. The horizontal leg of each bell crank lever is connected by a link 35, with a respective upper link 22 of the blade, the link 35 being pivotally connected to the bell crank lever by a pivot pin 36 and being connected to the pivot pin 24 of the link 22. Thus, when the bell crank levers are rocked, the blade will be raised ners which may be constructed offboards, if deor lowered.

The beams I 1 are provided with upstanding respective arms 31 which are equipped at'the upper ends with respective travelling nuts 38 which are pivoted to the arms, as shown at 39. Feed shafts 40 are disposed longitudinally above respective beams I1 and are threadedly engaged through the travelling nuts. The vertical legs of the bell crank levers 3| are equipped with smooth bore nuts 4|, which are pivoted to the legs, as shown at 42. Stop collars 43 are fixed to the feed shafts at the opposite ends of the nuts 4| to prevent endwise shifting of the feed shafts in the nuts. Each feed shaft terminates at the rear end in a respective crank handle 44. When the crank handles 44 are rotated, the bell crank levers 43 will be rocked by threading of the feed shafts through the travelling nuts 38 to adiust the blade 2| vertically.

In normal operation of the device, as the runners I advance on the ground, the supporting wheels |4 encounter humps indicated at 45 in Figure 2, and will encounter depressions indicated at 46 in Figure 3.v When the supporting wheels rise in passing over a hump 45, the feed shafts 40 will be moved endwise forwardly and rock the bell crank levers 3| forwardly with resultant lowering of the blade 2| as shown in Figure 2. Conversely, when the supporting wheels drop into a depression 46, the feed shafts will be moved endwise rearwardly and rock the bell crank levers rearwardly with resultant raising of the blade as shown in Figure 3. In this manner humps are reduced and depressions filled to level off the ground.

The means for rocking the levers 36 to adjust the angular inclination of the blade 2| comprises a pair of feed shafts 41 having respective travelling nuts 48 pivotally connected, as shown at 49, to the upperends of the levers 26. The feed shafts are provided with respective smooth bore nuts 50 and are pmvided with stop collars at the opposite ends of the nuts to prevent endwise shifting of the feed shafts. The nuts are pivoted, as shown at 52, to the upper ends of upstanding bracket arms 53 which are bolted, as shown at 54, to the runners I0. The feed shafts are equipped at the rear ends with respective crank handles 55. When the crank handles are turned, the travelling nuts 48 will be moved longitudinally of the feed shafts 41 to move the links 20 and 23 endwise in opposite directions to vary the inclination of the blade to the ground.

A head board 56 is disposed transversely between the front ends of the runners i0 and projects below the runners to serve as a gauge for controlling the penetration of the runners into soft ground. A pair of lower links 51 extend longitudinally of the runners and are pivotally connected at the rear ends to the runners as shown at 58. 'I'he links are pivotally connected at the front ends to the rear face of the head board as shown at 59.

A pair of bell crank levers 60 are pivotally connected at their elbows to the runners above the links 51, as shown at 6|. The bell crank levers are pivotally connected to the rear face of the head board as shown at 62. Threaded rods 63 are pivotally secured at the forward ends to the bell crank levers, as shown at 64, and they are engaged through openings in respective brackets 65, which are secured to the runners by bolts 66, which are also secured to the upstanding brackets I8 by bolts 61. Nuts 68 are threaded on the rods on opposite sides of the brackets 65 to adjust the position of the bell crank levers 6l to control the vertical adjustment of the head board 66.

A tail board 69 extends transversely between the rear ends of the runners Il and is pivotally secured to the runners by respective angular brackets 1II, which are pivoted to the runners in advance of the tail board by pivot pins 1|. The angular brackets are provided with upstanding levers 12 having respective rods 13 pivotally connected at the rear ends thereto, as shown at 14. The front ends of the rods slidably project through openingsv in brackets 15 and the front ends are threaded and equipped with stop nuts 16 which engage the front sides of the brackets 15. Helical springs 11 are sleeved on the rods. When the tail board 69 strikes an obstruction, it will be dislodged upwardly on its pivot 1| thereby compressing the springs 11 as the rods 13 slide forwardly through the brackets 15. When the obstruction has been passed, the springs 11 return the tail board to normal vertical position.

The front and rear ends of the runners are spaced apart by respective transverse brace rods 18 and 19, the latter being disposed adjacent to the tail board 69 and the former being disposed adjacent draft appliances to which a tractor or other means of propulsion may be attached.

Since the operation of the parts has been described as the description of the parts progressed, it is thought that the invention will be iiciently understood without further explana- What is claimed is:

l. A land leveler comprising a pair of spaced runners, head and tail boards at the ends of the runners forming gauges to limit penetration of the runners in soft ground, means for adjusting the head and tail boards vertically, brackets carried by the runners, a scraper blade between the runners, a bell crank lever connecting the scraper blade to one of the brackets, a pair of ground engaging wheels disposed laterally of the runners, beams pivotally connecting the wheels to the other of the brackets, a shaft having a connection with the bell crank lever, and an arm carried by the beams having a connection with the shaft, the arm, the shaft and the bell crank lever moving the wheels and blade vertically in opposite directions as the wheels ride over inequalities in the ground to level off `the ground.

2. A land leveler comprising a pair of spaced runners, a pair of brackets extending upwardly from the runners near one end thereof, a scraper blade, superposed links pivotally connected at vertically spaced points to the blade, a vertically disposed lever carried by the runners, said links being connected at the rear ends to said lever, a bell crank lever carried by one of said brackets connected to the uppermost link to elevate or depress the blade when the bell crank lever is rocked, a pair of beams pivotally connected to the other of said brackets in advance of the blade, ground engaging wheels disposed laterally of the runners and carried by the free ends of said beams, an arm extending upwardly from one of said beams, and a shaft pivotally connected to the upper end of said arm and pivotally connected to the bell crank lever, said shaft being movable endwise by said arm to depress the blade when the ground wheels are elevated on a hump, said shaft being moved endwise in the opposite direction to elevate the blade when the ground wheels encounter a depression.

3. The structure as of claim 2 and in which said lever is pivotally connected to one of the runners intermediate said superposed links and adapted to be rocked on its pivot to move the links endwise oppositely to each other for varying the inclination of the scraper blade.

4. A landv leveler comprising a pair of spaced runners, brackets rising from the runners, beams pivoted to the upper ends of the brackets. ground engaging wheels carried by the rear ends of the beams laterally of the runners, brackets extending upwardly from the runners in rear of the ground wheels, bell crank levers carried by the brackets, a scraper blade disposed between the runners in rear of the ground wheels, links securing the scraper blade to the bell crank lever, shafts extending longitudinally above the beams having the forward ends threaded, travelling nuts on the shafts, arms extending upwardly from the beams pivotally secured to the travelling nuts, smooth bore nuts on the shaft at the rear end thereof, collars preventing endwise movement of the shafts through the smooth bore nuts, crank handles on the rear ends of the shafts for turning the shafts to feed the shafts endwise through the travelling nuts for adjust; ing the blade vertically, said shafts connecting the blade to the ground wheels for simultaneous movement in opposite directions vertically when the ground wheels encounter inequalities in the ground. y

WILLIAM F. LETHLEAN. 

